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51.
茶毛虫黑卵蜂产卵刺激素的研究   总被引:7,自引:0,他引:7  
采用改进的培养皿法制成人工寄主卵,研究了茶毛虫黑卵蜂对产卵刺激素的行为反应.结果表明,不论人工寄主卵内测试液是水还是寄主卵浆液,只要卵表涂有识主利它素(卵块抽提物),黑卵蜂就对其进行检查和刺探.但是,只有当测试液为寄主卵浆液时才会表现出持续长时间的产卵反应,这说明寄主卵浆液中含有刺激雌蜂产卵的产卵刺激素.经对产卵刺激素的分离、纯化和鉴定,产卵刺激素含有多种成分,由12种蛋白质组分、3种糖和15种游离氨基酸组成.  相似文献   
52.
湖南省茶树害虫寄生性小蜂和细蜂调查   总被引:1,自引:0,他引:1  
调查湖南茶树害虫寄生性小蜂和细蜂,共获25种,其中6种蜂是中国新记录种,5种蜂的寄主是新寄主.本文报道了10科,25种寄生蜂的名录;分别记述了12种寄生蜂的形态(有2种寄生蜂的形态描述略)、寄主及分布.  相似文献   
53.
Summary

Studies on the efficacy in pigs of low level in‐feed medication with the anthelmintic thiophanate at a minimum intake of 6 mg/kg/day for fourteen days are reported. A trial was conducted to compare a group of medicated fattening pigs with a similar unmedicated group on premises known to have a high challenge of Ascaris spp. Daily growth rate was improved whilst feed conversion ratio and the liver condemnation rate were reduced in the treatment group.

Routine medication of a whole herd using this regime contributed to a great improvement of the herd production when assessed by the above criteria. User studies in various geographical areas of the Netherlands involving 1500 adult pigs and 1200 fattening pigs medicated with thiophanate in‐feed for fourteen days demonstrated that the compound eliminated the faecal worm egg output and was readily accepted and tolerated by pigs.  相似文献   
54.
《African Zoology》2013,48(2):392-394
Interference competition for nectar sources has been repeatedly described between hummingbirds and various insects, but rarely recorded in other nectari-vorous birds. We observed aggressive behaviour by African sunbirds (Cinnyris reichenowi and Cinnyris bouvieri) defending the nectar plant Hypoestes aristata against carpenter bees (Xylocopa caffra and Xylocopa inconstans) in the Bamenda Highlands, Cameroon. During 200 hours of observation, we recorded 38 cases of the sunbirds attacking carpenter bees; all these intrusions occurred only in the flower-richest patches of the plant. We predict that similar aggressive interactions will occur between other Old World nectarivorous birds and insects. Such interference competition between distantly related taxa could have an important impact on the evolution of pollination systems.  相似文献   
55.
全球农作物蜜蜂授粉概况   总被引:9,自引:2,他引:7  
蜜蜂是自然界最主要的授粉昆虫,在保持生物多样性和维持生态系统平衡方面发挥着极为重要的作用,尤其是为农作物授粉,具有重要的经济价值和社会效应。本文主要从蜜蜂在生态系统中的作用、蜜蜂授粉在全球农业生产中的地位、发达国家或地区蜜蜂授粉概括、世界农作物属性种植变化趋势和世界蜂群数量动态变化等方面阐述了全球农作物蜜蜂授粉现状,并分析了我国农作物蜜蜂授粉的现状、存在问题及应对措施。  相似文献   
56.
Hormesis, a biphasic dose response whereby exposure to low doses of a stressor can stimulate biological processes, has been reported in many organisms, including pest insects when they are exposed to low doses of a pesticide. However, awareness of the hormesis phenomenon seems to be limited among bee researchers, in spite of the increased emphasis of late on pollinator toxicology and risk assessment. In this commentary, we show that there are several examples in the literature of substances that are toxic to bees at high doses but stimulatory at low doses. Appreciation of the hormetic dose response by bee researchers will improve our fundamental understanding of how bees respond to low doses of chemical stressors, and may be useful in pollinator risk assessment. © 2015 Society of Chemical Industry  相似文献   
57.
Despite scientific and media attention on pollinator declines, there is still only a rudimentary understanding of the response of bees—the most important group of pollinators worldwide—to ongoing land use changes. Euglossine bees are an ecologically important Neotropical clade of forest-dependent pollinators. Despite the fact that euglossines are well studied relative to other groups of tropical bees, only three previous studies, all from Brazil, address the response of euglossines to forest fragmentation. In this study, I tripled the maximum sample size of previous efforts by sampling male euglossines in 22 forest fragments ranging in area from 0.25 ha to 230 ha in southern Costa Rica, using chemically baited Van Someren traps. Abundance of euglossine bees was significantly positively related to forest fragment size, negatively related to shape (edge:area ratio), and marginally related to fragment isolation. Euglossine species richness showed similar, but weaker trends: richness was significantly positively related to the quantity of forest edge, marginally negatively related to fragment area, and not related to fragment isolation. The positive relationship between euglossine richness and abundance and forest fragment edge is consistent with other studies that have found high euglossine density in secondary or disturbed forest. The data suggest that individual euglossines move between forest fragments, as has been shown in other systems. Still, forest fragmentation appears to affect euglossine bees more strongly than other bee groups in the study region. Their large flight range and positive relationship with forest edges may help to buffer the negative effects of fragmentation, allowing euglossines to utilize even the very smallest forest fragments in the study area.  相似文献   
58.
The increasing spread of invasive alien plants has changed biodiversity throughout the world. To date research in this area has focused on how invasive plant species affect pollinator behaviour, but there is a lack of data on the impact that alien plant species have on wild pollinator populations. Since their introduction in the 19th century, and rapid spread after the 1950s, alien goldenrods (Solidago canadensis, Solidago gigantea) have been among the most successful invasive plant species in Europe. We studied the effects of goldenrods on wild pollinator communities in SE Poland. The abundance, species richness and diversity of wild bees, hoverflies and butterflies were compared between wet meadows invaded by goldenrod (10 transects) and non-invaded controls (10 transects). Furthermore, we compared the plant diversity and average cover between the two groups of sites. Invasion of goldenrods had a very strong negative effect on wild pollinator diversity as well as abundance. Plant diversity and average cover were also negatively affected by goldenrod invasion. Wild pollinators were grouped according to their nesting and food specialization, but none were resistant to the invasion, indicating that introduced goldenrod may affect the entire wild pollinator community. Our study emphasises the urgent need to develop specific protection plans for wild pollinators in habitats threatened by foreign plants and we call for the introduction of programs to stop the invasion of goldenrod not only in Poland, but also on a continental scale.  相似文献   
59.
60.
为研究茶花蜂花粉中吡虫啉及其代谢物残留对蜜蜂安全的影响,在茶树始花期喷施10%吡虫啉可湿性粉剂,测定防虫网大棚内茶花蜂花粉样品中吡虫啉及其代谢物吡虫啉烯烃、吡虫啉脲、6-氯烟酸的残留量,并结合现有毒理学数据和风险评估模型进行评估。结果表明:以风险商值(Risk Quotient,RQsp)进行初级风险评估时,吡虫啉在茶树上的使用对蜜蜂具有不可接受的急性接触风险;以暴露量/毒性(Exposure toxicity ratio,ETR)进行暴露评估时,蜜蜂急性经口风险可接受,而成蜂致畸风险在药后13 d内均不可接受。此外,ETR的评价结果还表明,吡虫啉对蜜蜂风险主要源于吡虫啉母体,代谢物的风险占比低于2%。基于风险评价结果以及本实验的局限性,对吡虫啉在茶树上的实际使用风险仍需开展进一步试验。  相似文献   
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